Hi…
I recently follow an youtube tutorial to create a simple chart to launch in revit window, but unfortunately it was crashed, then I reopen that file again in dynamo… but, all the nodes has gone or disappeared in my screen and left only wires. in that case i were using dynamo coreruntime ver 2.1 in revit 2020.
as seen as followed…

This is often due to an incompatible Revit add-in. Try disabling all Revit add-ins and see if the file opens cleanly. If so start adding the add-ins back until you find the conflict. Once you identify the culprit, ensure it’s all the way up to date, and if so reach out to the creator to have it updated, or omit it to prevent the conflict.

I was tried to use archi-lab.mandrill plugin to create a bar chart, I’ve found that if I close the report window, then my chart nodes everything become error and crashed, then I tried to fix it in 2 ways, one is I remove all archi-lab plugin and reinstall again to make it work. second is to close both dynamo and revit or restart windows, because of certain process of that archi-lab plugin was still running/processing in the back scene, if im not mistaken it’s called Essential Object Process or Eos.exe make it always conflict.
So, in order to avoid any crashed I can’t close that report window (bar chart) from archi-lab mandril until I finished everything in dynamo graph before jump into another new file.